Pilot-scale Study Of SMBBR Combined Process For Treating Unsymmetrical Dimethylhydrazine Wastewater

Facing the increasingly serious environmental pollution problem and the increasing amount of unsymmetrical dimethylhydrazine wastewater,the society has more urgent needs for the treatment technology and process of unsymmetrical dimethylhydrazine wastewater.At the same time,a large amount of wastewater generated during the production,transportation,storage and use of unsymmetrical dimethylhydrazine will also cause great harm to the environment and human health.Therefore,there is an urgent need for a suitable and efficient unsymmetrical dimethylhydrazine wastewater treatment process.In this study,the SMBBR combined process was used to treat unsymmetrical dimethylhydrazine wastewater in order to meet the national emission standards for aerospace propellant water pollutants("Aerospace Propellant Water Pollutant Discharge and Analysis Method"(GB14374-93)),and it is running stably At this stage,the SMBBR combined process has a good treatment effect on ammonia nitrogen,chemical oxygen demand,total phosphorus,unsymmetrical dimethylhydrazine and other wastewater indicators in dimethylhydrazine wastewater,with a hydraulic retention time of 10 d,a filler filling rate of 45%,and initial Under the working conditions with a concentration of about 50mg/L,a temperature between 20-25°C and a carbon source dosage of 100mg/L,the SMBBR combined process has an effect on ammonia nitrogen,chemical oxygen demand,total phosphorus,and The removal rate of methylhydrazine eventually remained above 99%,96%,95%,99%,which reached the national standard for the discharge of unsymmetrical dimethylhydrazine wastewater.Analysis of the microbial flora structure of the biofilm samples in different reactors on the Illumina Miseq sequencing platform showed that the diversity of microbes gradually increased with the order of the process flow,and the relative abundance of Actinomycetes at the gate level The largest,this species of bacteria has improved the growth environment of microorganisms and promoted the growth of microorganisms through different metabolic methods;the dominant species in the sample are concentrated in Pseudo Nocardia,Millisia,Rhodococcus.In addition,norank-f-Saprospiraceae and AAP99 plays a very important role in the degradation of unsymmetrical dimethylhydrazine in the system.During the cultivation and screening of microorganisms on the biofilm,a Bacillus strain was isolated,and the highest tolerance value of the strain was measured to be 100 mg/L.Therefore,the SMBBR combination process can be applied well below the concentration The treatment of 100mg/L unsymmetrical dimethylhydrazine wastewater,which provides a reference for the application of this process in the treatment of unsymmetrical dimethylhydrazine wastewater.Moreover,the success of this pilot experiment also shows that the use of SMBBR and its combined process for the treatment of unsymmetrical dimethylhydrazine wastewater provides a practical new way.